Obama is 'fired up' for Clinton as Democrats seek to unify party

By Amanda Becker and Emily Stephenson WASHINGTON (Reuters) – U.S. President Barack Obama formally endorsed Hillary Clinton’s White House bid on Thursday and called for Democrats to unite behind her after a protracted battle with Bernie Sanders for the party nomination. U.S. Senator Elizabeth Warren of Massachusetts also backed Clinton on Thursday, telling MSNBC’s “The Rachel Maddow Show” that presumptive Republican presidential nominee Donald Trump was “a genuine threat to the country.” Clinton, the presumptive Democratic nominee, said it “means the world” to her that Obama had her back in a bruising campaign for the Nov. 8 election.